Assessment of a Tele-education System to Enhance Retinopathy of Prematurity Training by International Ophthalmologists-in-Training in Mexico.

PURPOSE: To evaluate a tele-education system developed to improve diagnostic competency in retinopathy of prematurity (ROP) by ophthalmologists-in-training in Mexico. DESIGN: Prospective, randomized cohort study. PARTICIPANTS: Fifty-eight ophthalmology residents and fellows from a training program in Mexico consented to participate. Twenty-nine of 58 trainees (50%) were randomized to the educational intervention (pretest, ROP tutorial, ROP educational chapters, and posttest), and 29 of 58 trainees (50%) were randomized to a control group (pretest and posttest only). METHODS: A secure web-based educational system was created using clinical cases (20 pretest, 20 posttest, and 25 training chapter-based) developed from a repository of over 2500 unique image sets of ROP. For each image set used, a reference standard ROP diagnosis was established by combining the clinical diagnosis by indirect ophthalmoscope examination and image-based diagnosis by multiple experts. Trainees were presented with image-based clinical cases of ROP during a pretest, posttest, and training chapters. MAIN OUTCOME MEASURES: The accuracy of ROP diagnosis (e.g., plus disease, zone, stage, category) was determined using sensitivity and specificity calculations from the pretest and posttest results of the educational intervention group versus control group. The unweighted kappa statistic was used to analyze the intragrader agreement for ROP diagnosis by the ophthalmologists-in-training during the pretest and posttest for both groups. RESULTS: Trainees completing the tele-education system had statistically significant improvements (P < 0.01) in the accuracy of ROP diagnosis for plus disease, zone, stage, category, and aggressive posterior ROP (AP-ROP). Compared with the control group, trainees who completed the ROP tele-education system performed better on the posttest for accurately diagnosing plus disease (67% vs. 48%; P = 0.04) and the presence of ROP (96% vs. 91%; P < 0.01). The specificity for diagnosing AP-ROP (94% vs. 78%; P < 0.01), type 2 ROP or worse (92% vs. 84%; P = 0.04), and ROP requiring treatment (89% vs. 79%; P < 0.01) was better for the trainees completing the tele-education system compared with the control group. Intragrader agreement improved for identification of plus disease, zone, stage, and category of ROP after completion of the educational intervention. CONCLUSIONS: A tele-education system for ROP education was effective in improving the diagnostic accuracy of ROP by ophthalmologists-in-training in Mexico. This system has the potential to increase competency in ROP diagnosis and management for ophthalmologists-in-training from middle-income nations.

Plus Disease in Retinopathy of Prematurity: A Continuous Spectrum of Vascular Abnormality as a Basis of Diagnostic Variability.

PURPOSE: To identify patterns of interexpert discrepancy in plus disease diagnosis in retinopathy of prematurity (ROP). DESIGN: We developed 2 datasets of clinical images as part of the Imaging and Informatics in ROP study and determined a consensus reference standard diagnosis (RSD) for each image based on 3 independent image graders and the clinical examination results. We recruited 8 expert ROP clinicians to classify these images and compared the distribution of classifications between experts and the RSD. PARTICIPANTS: Eight participating experts with more than 10 years of clinical ROP experience and more than 5 peer-reviewed ROP publications who analyzed images obtained during routine ROP screening in neonatal intensive care units. METHODS: Expert classification of images of plus disease in ROP. MAIN OUTCOME MEASURES: Interexpert agreement (weighted κ statistic) and agreement and bias on ordinal classification between experts (analysis of variance [ANOVA]) and the RSD (percent agreement). RESULTS: There was variable interexpert agreement on diagnostic classifications between the 8 experts and the RSD (weighted κ, 0-0.75; mean, 0.30). The RSD agreement ranged from 80% to 94% for the dataset of 100 images and from 29% to 79% for the dataset of 34 images. However, when images were ranked in order of disease severity (by average expert classification), the pattern of expert classification revealed a consistent systematic bias for each expert consistent with unique cut points for the diagnosis of plus disease and preplus disease. The 2-way ANOVA model suggested a highly significant effect of both image and user on the average score (dataset A: P < 0.05 and adjusted R2 = 0.82; and dataset B: P < 0.05 and adjusted R2 = 0.6615). CONCLUSIONS: There is wide variability in the classification of plus disease by ROP experts, which occurs because experts have different cut points for the amounts of vascular abnormality required for presence of plus and preplus disease. This has important implications for research, teaching, and patient care for ROP and suggests that a continuous ROP plus disease severity score may reflect more accurately the behavior of expert ROP clinicians and may better standardize classification in the future.

Plus Disease in Retinopathy of Prematurity: Improving Diagnosis by Ranking Disease Severity and Using Quantitative Image Analysis.

PURPOSE: To determine expert agreement on relative retinopathy of prematurity (ROP) disease severity and whether computer-based image analysis can model relative disease severity, and to propose consideration of a more continuous severity score for ROP. DESIGN: We developed 2 databases of clinical images of varying disease severity (100 images and 34 images) as part of the Imaging and Informatics in ROP (i-ROP) cohort study and recruited expert physician, nonexpert physician, and nonphysician graders to classify and perform pairwise comparisons on both databases. PARTICIPANTS: Six participating expert ROP clinician-scientists, each with a minimum of 10 years of clinical ROP experience and 5 ROP publications, and 5 image graders (3 physicians and 2 nonphysician graders) who analyzed images that were obtained during routine ROP screening in neonatal intensive care units. METHODS: Images in both databases were ranked by average disease classification (classification ranking), by pairwise comparison using the Elo rating method (comparison ranking), and by correlation with the i-ROP computer-based image analysis system. MAIN OUTCOME MEASURES: Interexpert agreement (weighted κ statistic) compared with the correlation coefficient (CC) between experts on pairwise comparisons and correlation between expert rankings and computer-based image analysis modeling. RESULTS: There was variable interexpert agreement on diagnostic classification of disease (plus, preplus, or normal) among the 6 experts (mean weighted κ, 0.27; range, 0.06-0.63), but good correlation between experts on comparison ranking of disease severity (mean CC, 0.84; range, 0.74-0.93) on the set of 34 images. Comparison ranking provided a severity ranking that was in good agreement with ranking obtained by classification ranking (CC, 0.92). Comparison ranking on the larger dataset by both expert and nonexpert graders demonstrated good correlation (mean CC, 0.97; range, 0.95-0.98). The i-ROP system was able to model this continuous severity with good correlation (CC, 0.86). CONCLUSIONS: Experts diagnose plus disease on a continuum, with poor absolute agreement on classification but good relative agreement on disease severity. These results suggest that the use of pairwise rankings and a continuous severity score, such as that provided by the i-ROP system, may improve agreement on disease severity in the future.

Multimodality treatment of intrahepatic cholangiocarcinoma: A review.

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary hepatic cancer in the United States. Currently, curative treatment involves aggressive surgery. Chemotherapy and radiation treatments have been used for unresectable tumors with some success. Optimizing the use of current and developing novel multimodality treatment for iCCA is essential to improving outcomes.

Postmarketing Analysis of a Novel, Cordless Ultrasonic Dissector.

Introduction Tissue dissection and vessel sealing is performed using a variety of energy sources and surgical devices. We describe the postmarketing analysis of a cordless ultrasonic dissector and vessel sealer in a series of general and gynecological procedures. Methods Patients were prospectively screened and consented for participation. Data collected included demographics, device activations/seals and failures, and patient complications. Surgeons were surveyed following each case. Data was analyzed using standard statistical methods. Results A total of 110 patients were consented and participated in the study. The most frequently performed procedures were bilateral salpingo-oophorectomy (n = 48) and total laparoscopic hysterectomy (n = 36). Mean age was 54.2 years and 79.2% were female. The most frequent number of device activations per case was between 26 and 50 (36.6%). Five failed seals occurred out of 4858 total estimated seals (0.11%). Failed seals were felt to be due to thickened, scarred tissue not amenable to device compression. There were no patient intraoperative complications related to the device itself. Overall, surgeons felt the device was extremely easy to use (97.6%) and no visual obstruction due to steam from the device was encountered (95%). Ninety-five percent of surgeons felt the device was beneficial for soft tissue dissection and vessel sealing. Conclusion Sonicision is safe and effective for use in dissection of soft tissues and vessel sealing in a variety of laparoscopic and open procedures. In this study, there were no complications related to the device itself. The remarkable cordless design of this device enhances its ease of use with overall excellent effectiveness.

Optimal ablation volumes are achieved at submaximal power settings in a 2.45-GHz microwave ablation system.

INTRODUCTION: Local ablative therapies, including microwave ablation (MWA), are common treatment modalities for in situ tumor destruction. Currently, 2.45-GHz ablation systems are gaining prominence because of the shorter application times required. The aims of this study were to determine optimal power and time to ablation volume (AbV) ratios for a new 1.8-mm-2.45-GHz antenna using ex vivo tissue models. METHODS: The 1.8-mm-2.45-GHz Accu2i MWA system was employed to perform ablations in bovine liver, porcine muscle, and porcine kidney ex vivo. Whole tissues were prewarmed (35°C) and multiple ablations performed at power settings of 60 to 180 W for 2- to 6-minute time intervals. Postablation, tissues were dissected, AbVs calculated, and correlations to power and time settings made. RESULTS: Significant increases in AbV were measured between each of the time points for a constant power setting in all 3 tissues. Increasing power settings led to significant increases in AbV at power settings ≤140 W. However, no significant increase in AbV was obtained at power settings >140 W. CONCLUSIONS: Optimal efficiency for MWA using a new 1.8-mm-2.45-GHz system is achieved at settings of ≤140 W for 6 minutes in a range of ex vivo tissue and no additional benefit occurs by increasing the power setting to 180 W in these tissues.

Outcomes of surgical resection and loco-regional therapy in patients with stage 3A hepatocellular carcinoma: a retrospective review from the national cancer database.

OBJECTIVES: In advanced stages, hepatocellular carcinoma (HCC) is often associated with major vascular involvement (cava, portal vein). The aim of the present study was to analyse the role of surgical resection (SR) and loco-regional therapy (LRT) in these advanced stage patients to determine if there was a survival benefit. METHODS: The study is a retrospective analysis from the Commission on Cancer's National Cancer Data Base (NCDB) from 1998 to 2011. In total, 148,882 patients with liver cancer were identified, of which 126,984 had HCC. Of these, 64,264 patients (1998-2006) had 5-year survival data available and 8825 patients had Stage 3A disease based on AJCC classification. Of these patients, 884 had SR, 771 had LRT and 7170 patients had neither intervention. Kaplan-Meier curves and log-rank tests were used for statistical analysis. RESULTS: Eight thousand eight hundred and twenty-five patients met analysis criteria. The mean age (years) in the SR, LRT and no intervention group were 62.5, 64.3 and 64.2, respectively. Most patients were males in all three groups (77.5%, 74.5% and 68.1%). The mean tumour size (cm) in the three groups was 9.8, 6.4 and 8.4, respectively. SR and LRT were primarily performed in major academic and comprehensive cancer programmes compared with community cancer programmes and other centres (SR: 93% versus 7%; LRT: 94.6% versus 5.4%). The median 5-year survival (months) was 26.6 in SR, 16.5 in LRT and 4.8 in the no intervention group (P < 0.0001). CONCLUSION: A SR and LRT offer a survival benefit in select patients diagnosed with Stage 3A HCC.

Laparoscopic microwave ablation of human liver tumours using a novel three-dimensional magnetic guidance system.

BACKGROUND: Accurate antenna placement is essential for effective microwave ablation (MWA) of lesions. Laparoscopic targeting is made particularly challenging in liver tumours by the needle's trajectory as it passes through the abdominal wall into the liver. Previous optical three-dimensional guidance systems employing infrared technology have been limited by interference with the line of sight during procedures. OBJECTIVE: The aim of this study was to evaluate a newly developed magnetic guidance system for laparoscopic MWA of liver tumours in a pilot study. METHODS: Thirteen patients undergoing laparoscopic MWA of liver tumours gave consent to their participation in the study and were enrolled. Lesion targeting was performed using the InnerOptic AIM™ 3-D guidance system to track the real-time position and orientation of the antenna and ultrasound probe. RESULTS: A total of 45 ablations were performed on 34 lesions. The median number of lesions per patient was two. The mean ± standard deviation lesion diameter was 18.0 ± 9.2 mm and the mean time to target acquisition was 3.5 min. The first-attempt success rate was 93%. There were no intraoperative or immediate postoperative complications. Over an average follow-up of 7.8 months, one patient was noted to have had an incomplete ablation, seven suffered regional recurrences, and five patients remained disease-free. CONCLUSIONS: The AIM™ guidance system is an effective adjunct for laparoscopic ablation. It facilitates a high degree of accuracy and a good first-attempt success rate, and avoids the line of site interference associated with infrared systems.

Microwave ablation for hepatic malignancies: a multiinstitutional analysis.

OBJECTIVE: This study hypothesized that tumor size, number of tumors, surgical approach, and tumor histology significantly affected microwave ablation (MWA) success and recurrence-free survival. BACKGROUND: Although many hepatobiliary centers have adopted MWA, the factors that influence local control are not well described. METHODS: Consecutive patients with hepatic malignancy treated by MWA were included from 4 high-volume institutions (2003-2011) and grouped by histology: hepatocellular carcinoma (HCC), colorectal liver metastases, neuroendocrine liver metastases, and other cancers. Independent significance of outcome variables was established with logistic regression and Cox proportional hazards models. RESULTS: Four hundred fifty patients were treated with 473 procedures (139 HCC, 198 colorectal liver metastases, 61 neuroendocrine liver metastases, and 75 other) for a total of 875 tumors. Median follow-up was 18 months. Concurrent hepatectomy was performed in 178 patients (38%), and when performed was associated with greater morbidity. Complete ablation was confirmed for 839 of 865 tumors (97.0%) on follow-up cross-sectional imaging (10 were unevaluable). A surgical approach (open, laparoscopic, or percutaneous) had no significant impact on complication rates, recurrence, or survival. The local recurrence rate was 6.0% overall and was highest for HCC (10.1%, P = 0.045) and percutaneously treated lesions (14.1%, P = 0.014). In adjusted models, tumor size 3 cm or more predicted poorer recurrence-free survival (hazard ratio: 1.60, 95% CI: 1.02-2.50, P = 0.039). CONCLUSIONS: In this large data set, patients with 3 cm or more tumors showed a propensity for early recurrence, regardless of histology. Higher rates of local recurrence were noted in HCC patients, which may reflect underlying liver disease. There were no significant differences in morbidity or survival based on the surgical approach; however, local recurrence rates were highest for percutaneously ablated tumors.

Laparoscopic transgastric endolumenal cystogastrostomy and pancreatic debridement.

BACKGROUND: Cystogastrostomy is commonly performed for internal drainage of pancreatic pseudocysts (PP) and concomitant debridement of walled-off pancreatic necrosis (WOPN). While an open approach to cystogastrostomy is well established, an optimal minimally invasive technique continues to evolve. This laparoscopic transgastric endolumenal cystogastrostomy presented here allows for a large cystogastrostomy with complete debridement of necrosis and internal drainage through a minimally invasive approach. METHODS: We performed a retrospective review of 22 patients with symptomatic PP/WOPN treated with attempted laparoscopic transgastric endolumenal cystogastrostomy (Lap-TEC) and pancreatic debridement. Short- and long-term outcomes were assessed. RESULTS: From November 2006 to March 2013, a total of 22 Lap-TEC/pancreatic debridement procedures were attempted; 15 were completed laparoscopically. The median age of the cohort was 49.5 ± 12 years (range = 18-71), average body mass index = 29.1 kg/m(2), 77 % had an ASA score ≥ 3, and 10 were female. Gallstones were the most common etiology (50 %), and median time between initial presentation and surgery was 86 days (range = 0-360). Median operative time and estimated blood loss were 213 min and 100 cc, respectively. Forty-one percent of the patients were admitted to the ICU postoperatively and the average length of stay was 14 days (range = 4-50). Median follow-up was 2 months (range = 0-62.5), with one patient having a procedure-related complication. No other reoperations, late complications, or mortalities occurred. All patients had resolution of their symptoms and fluid collections. CONCLUSION: This technique of internal drainage via Lap-TEC and pancreatic debridement has been successful in achieving primary drainage and relieving symptoms of PP/WOPN with no mortality and minimal morbidity.

Fibrin sealants and topical agents in hepatobiliary and pancreatic surgery: a critical appraisal.

INTRODUCTION: Fibrin sealants and topical hemostatic agents have been used extensively in hepatobiliary and pancreatic (HPB) surgery to promote coagulation and clot formation decreasing the need for allogeneic blood transfusion and to act as tissue sealants, ideally preventing biliary, enteric, and pancreatic leaks. RESULTS: Current literature has demonstrated some favorable outcomes using many different products for application in the field of HPB surgery. However, critical findings exist demonstrating lack of reproducible efficacy or benefit. In all, many clinical trials have demonstrated effectiveness of fibrin sealants and other agents at reducing the need for intraoperative and postoperative blood transfusion. Ability to effectively seal tissues providing biliostatic effect or preventing postoperative fistula formation remains debated as definitive evidence is lacking. CONCLUSIONS: In the following invited review, we discuss current literature describing the use of topical agents and fibrin sealants in liver and pancreas surgery. We summarize major contemporary clinical trials and their findings regarding the use of these agents in HPB surgery and provide evidence from the preclinical literature as to the translation of these products into the clinical arena.

Survival analysis of patients with stage I and II hepatocellular carcinoma after a liver transplantation or liver resection.

INTRODUCTION: Liver transplantation (LT) is a treatment option in select patients with hepatocellular carcinoma (HCC). The aim of the present study was to compare survival in Stage I or II HCC patients undergoing either liver transplant (LT) or a liver resection (LR). METHOD: The study is a retrospective analysis of the National Cancer Data Base (1998-2011). In total, 148,882 patients with liver cancer were identified, of which 5-year survival data (1998-2006) were available for 64,227 patients. Patients were stratified by the American Joint Committee on Cancer (AJCC) clinical stage I and II. Kaplan-Meier curves and log-rank tests were used for statistical analysis. RESULTS: 3340 HCC patients met analysis criteria. Among stage I HCC, 860 had LT and 871 had LR. Among stage II HCC, 833 had LT and 776 LR. In stage I patients the median survival for LT and LR were 127.9 and 56.7 months, respectively, (P < 0.0001) and in stage II patients the median survival was 110.8 and 42.8 months (P < 0.0001). Unlike LT patients, LR patients with Stage I HCC had a longer median survival compared with Stage II patients (P = 0.0002). CONCLUSION: Liver transplantation offers a survival advantage compared with a liver resection among patients with Stage I and II HCC. LT is the best surgical treatment for early stage (I/II) HCC in patients with advanced fibrosis or cirrhosis, whereas LR provides equivalent outcomes to LT in patients without advanced fibrosis and should be considered as the first surgical option.

MyD88-dependent expansion of an immature GR-1(+)CD11b(+) population induces T cell suppression and Th2 polarization in sepsis.

Polymicrobial sepsis alters the adaptive immune response and induces T cell suppression and Th2 immune polarization. We identify a GR-1(+)CD11b(+) population whose numbers dramatically increase and remain elevated in the spleen, lymph nodes, and bone marrow during polymicrobial sepsis. Phenotypically, these cells are heterogeneous, immature, predominantly myeloid progenitors that express interleukin 10 and several other cytokines and chemokines. Splenic GR-1(+) cells effectively suppress antigen-specific CD8(+) T cell interferon (IFN) gamma production but only modestly suppress antigen-specific and nonspecific CD4(+) T cell proliferation. GR-1(+) cell depletion in vivo prevents both the sepsis-induced augmentation of Th2 cell-dependent and depression of Th1 cell-dependent antibody production. Signaling through MyD88, but not Toll-like receptor 4, TIR domain-containing adaptor-inducing IFN-beta, or the IFN-alpha/beta receptor, is required for complete GR-1(+)CD11b(+) expansion. GR-1(+)CD11b(+) cells contribute to sepsis-induced T cell suppression and preferential Th2 polarization.

Diet-induced obesity and ethanol impair progression of hepatocellular carcinoma in a mouse mesenteric vein injection model.

BACKGROUND: Hepatocellular carcinoma (HCC) is a rapidly increasing cancer whose known risk factors are chronic ethanol abuse, viral hepatitis infection, and aflatoxin exposure. Obesity, an emerging HCC risk factor, is reaching epidemic proportions in developed nations. This study investigated the effects of diet-induced obesity (DIO) and chronic ethanol consumption on HCC progression in mice in vivo. METHODS: In this study, C57BL/6 DIO mice and lean litter mates were maintained on a 60% (high-fat diet [HFD]) diet or a 10% (control diet [CD]) kcal% fat diet for 7 weeks before they were weaned to 10/20% ([v/v], alternating days) ethanol in drinking water (EtOH) or maintenance on drinking water (H(2)O) alone. Hepatic tumor formation was initiated by intrahepatic Hepa1-6 cell (6 × 10(6) cells) inoculation 6 weeks later via the mesenteric vein. RESULTS: The animals receiving the HFD showed decreased tumor incidence and area of hepatic foci versus the CD animals maintained on H(2)O alone. The action of EtOH suppressed tumor incidence further in both the CD and the HFD mice. Serologic analysis showed no significant differences in liver enzymes among the groups. Protein analysis demonstrated increased P450 2E1 (CYP2E1) in the groups maintained on EtOH, an effect exacerbated by HFD. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis demonstrated increased tumor necrosis factor-alpha (TNF-α) expression in HFD HCC mice (H(2)O and EtOH) concomitant with decreased transforming growth factor-beta (TGF-ß) expression. CONCLUSIONS: Although obesity and EtOH consumption are known risk factors for HCC initiation and development, the data in this study suggest that these factors impair progression of established tumors within the liver.

Obesity, but not ethanol, promotes tumor incidence and progression in a mouse model of hepatocellular carcinoma in vivo.

BACKGROUND: Hepatocellular carcinoma (HCC) is a major global health burden. Although chronic, heavy alcohol abuse is an established risk factor for HCC, obesity is emerging as an increasingly important factor in HCC development. Given that other risk factors for HCC act synergistically to promote tumorigenesis, we investigated the effects of diet-induced obesity and chronic ethanol consumption on tumor progression. METHODS: A diethylnitrosamine (DEN) mouse model of HCC was established and mice randomized to control (CD; 10 % kcal% fat) or high fat (HFD; 60 % kcal% fat diet) at 5 weeks of age. At 35 weeks, mice were randomized to 10/20 % ethanol (EtOH) in drinking water (alternate days), or drinking water (H2O) alone. Tumor incidence/size were measured and confirmed. Liver tissue was analyzed for oxidative stress and EtOH-metabolizing enzymes and serum analyzed for liver function and nutritional status. RESULTS: DEN treatment induced HCC formation in 60 % CD-H2O mice (6 of 10), an effect exacerbated by HFD (89 %). Tumors in HFD animals occupied significantly more of the liver than mice on CD. EtOH-feeding did not impact HCC incidence or tumor size. HFD resulted in increased liver injury and liver:body weight ratio regardless of EtOH consumption. Increased tumor incidence was associated with elevated hepatic oxidative stress in the absence of changes in intrinsic antioxidant (glutathione) levels. CONCLUSIONS: Obesity independently promoted HCC formation in the absence or presence of a known hepatocarcinogen (DEN), and enhanced both number and size of hepatic tumors independent of chronic EtOH consumption in mice.

Evaluation of an innovative, cordless ultrasonic dissector.

Ultrasonic thermal energy is commonly used for dissection and vessel ligation. This study compared HARMONIC ACE and Sonicision Cordless Ultrasonic Dissector (SCUD). The devices were used in an in vivo porcine model to coagulate 189 arteries up to 5 mm. Seal times were similar: SCUD, 5.2 ± 1.7 s; ACE, 4.9 ± 1.5 s (P = .20). Burst pressures for SCUD and AVE were 578 ± 284 and 605 ± 288 mm Hg, respectively (P = .48). Stratification by vessel diameter yielded similar results. In all, 17 applications resulted in seal failure on either the proximal or distal side, with no difference between SCUD (4.4%) and ACE (6.6%; P = .37). Histological examination of 48 specimens showed similar thermal spreads: 1.06 ± 0.05 versus 1.08 ± 0.05 mm for SCUD and ACE, respectively (P = .82). In 41 timed mesenteric transections, SCUD required 24.8 ± 4.9 s, which was significantly less than the 33.8 ± 5.4 s for ACE (P < .0001), with no bleeding in either group. SCUD and ACE showed similar vessel seal times, burst pressures, thermal spreads, and seal failure rates. SCUD was more efficient than ACE in mesenteric transection.

Microwave ablation using 915-MHz and 2.45-GHz systems: what are the differences?

OBJECTIVES: This study was conducted to evaluate differences between 915-MHz and 2.45-GHz microwave ablation (MWA) systems in the ablation of hepatic tumours. METHODS: A retrospective analysis of patients undergoing hepatic tumour MWA utilizing two different systems over a 10-month period was carried out. RESULTS: Data for a total of 48 patients with a mean age of 58 ± 1.24 years were analysed. A total of 124 tumours were ablated; 72 tumours were ablated with a 915-MHz system and 52 with a 2.45-GHz system. Mean tumour diameters were 1.7 ± 0.1 cm in the 915-MHz group and 2.5 ± 0.2 cm in the 2.45-GHz group (P < 0.01). Mean ablation time per burn was 8.1 ± 0.3 min in the 915-MHz group and 4.0 ± 0.1 min in the 2.45-GHz group (P < 0.01). The mean number of burns per lesion was 2.0 ± 0.1 in the 915-MHz group and 1.7 ± 0.1 in the 2.45-GHz group (P < 0.05). The mean ablation time per lesion was 9.7 ± 0.7 min in the 915-MHz group, and 6.6 ± 0.6 min in the 2.45-GHz group (P < 0.01). The 2.45-GHz system demonstrated a better correlation between ablation time and tumour size (r(2) = 0.6222) than the 915-MHz system; (r(2) = 0.0696). Mean total energy applied per lesion, and energy applied per cm, were greater with the 915-MHz system (P < 0.05 and P < 0.01, respectively). Total energy applied per lesion was similarly correlated for the 2.45-GHz (r(2) = 0.6263) and 915-MHz (r(2) = 0.7012) systems. Mean total energy applied per cm/min was greater with the 2.45-GHz system (P < 0.05). CONCLUSIONS: Both 915-MHz and 2.45-GHz MWA systems achieve reproducible hepatic tumour ablation. The 2.45-GHz system achieves equivalent, but more predictable and faster ablations using a single antenna system.

Adrenocortical carcinoma with intracaval extension to the right atrium: resection on cardiopulmonary bypass.

CASE PRESENTATION: A 28-year-old woman presented with dyspnea on exertion and elevated testosterone level. A 21 × 19 cm right adrenal mass was found invading the liver and inferior vena cava (IVC); tumor thrombus extended to the right atrium on transthoracic echocardiogram. OPERATIVE PROCEDURE: Median sternotomy and extended right subcostal incisions were made. Inferior surface of liver was mobilized and vessels to the tumor divided and packed. The IVC was isolated and cardiopulmonary bypass initiated. Tumor was excised from IVC and tumor thrombus extracted. After partial IVC wall resection, the venotomy was closed. The right atrium was explored for remaining thrombus. Segment 7 of the liver was resected with division of right hepatic vein. The patient was removed from bypass, and the cut surface of liver was reinforced with chromic sutures. Intraoperative ultrasound demonstrated no remaining tumor thrombus. Provisional closure was achieved with wound vac, and the next day, the patient's wound was closed primarily. OUTCOME: On postoperative day 3, the patient was extubated; she was discharged on day 12. Pathology revealed well-differentiated adenocarcinoma weighing 2.3 kg with negative surgical margins. Two months after surgery, she received radiation for suspected lumbar vertebral metastasis and initiated mitotane therapy. Follow-up surveillance scans showed no evidence of disease. DISCUSSION: Adrenocortical carcinoma is a rare malignancy presenting frequently in advanced stage with poor prognosis. Chemotherapy is often only moderately effective, while complete surgical resection is potentially curative. In this patient, excellent short-term outcome was achieved through radical surgical resection. We continue to monitor her closely for evidence of recurrence.

PD-1 expression by macrophages plays a pathologic role in altering microbial clearance and the innate inflammatory response to sepsis.

Sepsis, a leading cause of death worldwide, involves concomitant expression of an overzealous inflammatory response and inefficient bacterial clearance. Macrophage function is pivotal to the development of these two aspects during sepsis; however, the mechanisms underlying these changes remain unclear. Here we report that the PD-1:PD-L pathway appears to be a determining factor of the outcome of sepsis, regulating the delicate balance between effectiveness and damage by the antimicrobial immune response. To this end we observed that PD-1(-/-) mice were markedly protected from the lethality of sepsis, accompanied by a decreased bacterial burden and suppressed inflammatory cytokine response. To the extent that this is a macrophage-specific aspect of the effects of PD-1, we found the following: first, peritoneal macrophages expressed significantly higher levels of PD-1 during sepsis, which was associated with their development of cellular dysfunction; second, when peritoneal macrophages were depleted (using clodronate liposomes) from PD-1(-/-) mice, the animals' bactericidal capacity was lowered, their inflammatory cytokine levels were elevated, and protection from septic lethality was diminished; and third, blood monocytes from both septic mice and patients with septic shock shared markedly increased PD-1 levels. Together, these data suggest that PD-1 may not only be a dysfunctional marker/effector of macrophages/monocytes, but may also be a potential therapeutic target for designing measures to modulate the innate immune response, thereby preventing the detrimental effects of sepsis.

Real-time three-dimensional guided ultrasound targeting system for microwave ablation of liver tumours: a human pilot study.

OBJECTIVES: This study aimed to evaluate a novel three-dimensional ultrasound (US) guidance system for use in hepatic microwave ablation (MWA). METHODS: An in vitro assessment was performed in which users with different degrees of experience were evaluated for accuracy in targeting phantom lesions embedded in agar using US alone, or US in conjunction with the InVision™ System (IVS). An eight-patient pilot trial of the IVS was then performed in the setting of open hepatic MWA, in which lesions would otherwise have been targeted with conventional US. RESULTS: In vitro studies demonstrated that the IVS significantly improved targeting accuracy at all levels of operator experience (novice, beginner and expert). In the human trial, a total of 31 tumours were targeted and all lesions were hit in one pass, as assessed by independent US image observations. There were no adverse operative events; however, there was minor line-of-sight interference with the infra-red tracking mechanism when some lesions high on the dome of the liver were targeted. CONCLUSIONS: The IVS significantly increased the accuracy of complex targeting procedures of phantom lesions and enhanced targeting in an eight-patient clinical pilot study. During the accrual phase of this pilot study, the development of improved non-optical tracking hardware obviated the requirement to maintain a direct line of sight. The trial was then halted prematurely in order to focus on the application of the IVS utilizing this non-optical modality.